Immunological testing devices

ABSTRACT

A self-supporting plastic structure having a plurality of through-passages, each passage being of cross-sectional shape and area such that walls thereof provide a large amount of surface area relative to a substantially small amount of space cross-sectional area, each through passage having an upper funnel portion for receiving liquid, and a small outlet aperture of a smallness sufficient to effect a retention of liquid drop(s) within space of the through-passage by capillary action in the absence of additionally added fluid which by weight thereof forces liquid from the outlet aperture, and a separate washer structure seatable above the plastic structure and having a main liquid-containable vessel defined with a plurality of open outlets in the base thereof aligned for feeding contained liquid into separate ones of the through-passages simultaneously for the concurrent washing of each and all and/or for concurrent adding of further reagent or the like simultaneously concurrently to each and all.

THE SPECIFICATION

This invention relates to novel and improved equipment and methods forimmunological testing of typically antigens and antibodies.

BACKGROUND TO THE INVENTION

Prior to the present invention, typically for immunological testingthere have been employed non-toxic disposable plastic plates of plasticsuch as polyvinyl or polystyrene, for example, to which attachment tothe walls thereof by incubation is possible--as for example would occurupon addition of a fluid/liquid containing antigens to be counted and/oridentified. After the incubation period, a tedious procedure ofcarefully washing each separately of a plurality of vessels per plate isrequired to both avoid contamination of one from another and to washaway all non-attached antigens, such procedure being attempted andaccomplished by a variety of methods, all of which basically envolve theaddition of washing water, then the withdrawal of the washing water.Such procedures are time-consuming and require special care and skill,and the results are less than highly accurate because of the difficultyin effecting clean washing even though several washings may be includedwithin a procedure.

SUMMARY OF THE INVENTION

Accordingly, a primary object of the present invention is to obtainequipment and process(es) when are adaptable to a variety andmultiplicity of immunological tests and procedures, while avoidingproblems and difficulties of the type(s) described above.

Another object is to obtain a novel apparatus adaptable to speedytreatment and washings together with high efficiency and reliability inresults obtained, for both single test procedures for a single specimenor antigen or the like, and for conducting consurrently andsimultaneously a plurality of tests and/or specimens.

Another object is to obtain novel procedures utilizing such above-notedapparatus, achieving novel advantages together with avoidingdisadvantages and difficulties of prior apparatuses and procedures.

Another object is to obtain increased relative linking--(attaching) ofantigens and/or antibodies--as the case may be, to available wallsurface area relative to total volume of the vehicle-liquid, duringincubation, whereby less vehicle-liquid is required while intensityand/or positive-reading of the results is enhanced.

Another object is to obtain additional combination(s) of basic plateapparatus together with accessory washing apparatus coordinate in useand results, with the plate apparatus, for effecting reliable efficientand speeding testing of specimens of many different personssimultaneously and concurrently.

Another object is to obtain such plate apparatus, together withadditional container-type plate apparatus of a throw-away nature.

Another object is to obtain a plate apparatus of the improved greatersurface area relative to liquid volume-space, adaptable for detachablybreaking-off one specimen-passage structure from other adjacent ones,such that radioisotope counter may be utilized in the ascertaining ofthe presence and concentration of radioisotopes and other such tracers.

Other objects become apparent from the preceding and followingdisclosure.

One and more objects are obtained by the invention of which varioustypical but not exclusive embodiments described hereinafter are merelytypical, for purposes of understanding and illustration of theinvention, and as to preferred embodiments thereof.

Broadly the invention may be described as a plastic structure typicallyof polyvinyl and/or polystyrene, or other plastic material to which, asconventionally known, one or more of antigen or antibody or other agent,specimen, or reagent required for a particular test, will adhere, attachand/or link, as the case may be; and the plastic plate-like structuremust be self-supporting at least to an extent that when in its operativeposition for use, the base of through-passage upright and/or verticalpassage structure's lower end is suspended above a supporting surface tothereby avoid contamination from the surface and to allow flow of wateror other liquid to drain to the surface through the passage; and thecross-sectional area of space defined within the through-passage must besufficiently small and the length of the through-passage along a lengthlongitudinal axis thereof must be sufficiently elongated, such that wallsurface area within the through-passage in the area or vicinity of thesmall cross-section, is large in ratio to the cross-sectional area ofspace at that same vicinity, i.e. where the surface area relative tovolume, is large; and the through-passage has an upper structure whichis basically liquid-receivable--i.e. a funnel structure in function, forreceiving a particular liquid, avoiding the possibility of accidentaloverflow or spilling-over into an adjacent through-passage. It is to beunderstood, of course, that the support structure may be integral or notintegral, and may be in fact another apparatus such as a conventionalimmunological testing plate having a plurality of wells of containerspaces therein, on top of which the above-noted inventive appatatus maybe seated with the through-passage structures possiblyextending-downwardly into the well of container spaces, one per well ofcontainer space.

However, it is within the scope of the invention for there to be eithera mere single through-passage per entire apparatus, or in an embodimentfor use in handling large volumes of patients, and specimens thereof, aplurality of through-passages--and structures thereof, arranged incolumns and rows. For the embodiments having a plurality ofthrough-passage structures, of which the cross-sectional shapes thereofare preferably each of a dimension such that capillary action isretainable of liquid within the through-passage space thereof to obtainthe high ratio of surface area to liquid volume at that vicinity withinthe through-passage, a washing structure having a plurality of outletsmatchable with spaces, one per space, of the through-passages. Inanother preferred embodiment, there is provided either by integralstructure or alternatively by a separate plate-like structure, acollector structure having a small aperture in it, although there couldbe multiple apertures, such collector structure being possitioned inclose proximity with lower end(s) or portions of wall structures withineach respective through-passage, whereby drop(s) of liquid within and/orhanging to lower end(s) or portion(s) of the inner wall structure of thethrough-passage is facilitated in being tentatively retained thereat;upon adding of additional liquid and/or reagent, or the like, into thefunnel structure of that particular through-passage space, weight of theadded material forces liquid downwardly out of the through-passagespace, as well as out-of the one or more small apertures of thecollector structure. By virtue of such collector structure, the liquidvehicle--for example carrying the antigens initially, or at subsequentstages of treatment or testing steps, for retaining the antibody(ies)intermittently, improved attaching during incubation, and of linking,and the like are obtained, while never-the-less washing may be achievedby merely adding washing liquid (as water) to the funnel-structureportion of each of the through-passages; similarly, when adding reagentor the like, such excess merely passes downwardy and out of thecollector structure small aperture(s), but is retained until washedthrough by subsequent addition of other material or upon subsequentwashing.

In another combination, a washing apparatus includes a liquid containersuch as to obtain a large volume of water that may be poured easilythereinto, and the container structure has a plurality of bottom outletspreferably of funnel-like structure with the outlets aligned with andabove the funnel portions of the respective ones of the plurality ofthrough-passages, in order that simultaneously and concurrently theplurality may all be washed and/or a common liquid or reagent or thelike added to all of the plurality of through-passages. The containerstructure may be separate from the structure of the through-passages, oralternatively may be seatable thereon for intermittent use therewith.

In another preferred embodiment, the passage (through-passage) structuremay have scored lines or etched or compressed lines definingintermediate boreders between adjacent through-passage structures,thereby providing for easy breaking-off or shearing of one or morethrough-passage structures from other one or more through-passagestructures, such as is required when a single treated structure is to betested alone for the presence of radioactive isotopes or tracers or thelike, in radioimmunoassay or the like.

THE FIGURES

FIG. 1 illustrates in top and side perspective view a preferredcombination, shown in exploded view, of a plate-like collector structurehaving a plurality of collectors, over and into which fits the plasticthrough-passage structure having a plurality of separate through-passagestructures extending downwardly into the respective ones of thecollectors, and the liquid container and washing structure positionedand seated over the through-passage structure.

FIG. 2 illustrates a side-cross-sectional view in an in-part view of theFIG. 1 combination, in the seated states.

FIG. 3 illustrates a side-cross-sectional and exploded view of thecombination of the collector structure and the through-passagestructure, in an in-part view thereof.

FIG. 4 illustrates an alternate embodiment in side-cross-sectional andin-part view, of a unitary structure including both through-passagestructure and collector structure.

FIG. 5 illustrates a cross-sectional view as taken along line 5--5 ofFIG. 3.

FIGS. 6 and 7 illustrate alternative through-passage configurations aswould be viewed in cross-sectional views such as that of FIG. 5.

FIGS. 8 and 9 illustrate in axial-longitudinal cross-sectional viewsingle through-passage structure embodiments, as two typical alternateembodiments of that embodiment of the invention.

DETAILED DESCRIPTION

For purposes of description, reference is first made to theillustrations of FIGS. 1, 2, and 3, which disclose basically commonelements.

In particular, there is the collector structure 10 as an overall unit,having seated thereover and thereon the plastic through-passagestructure 11, and the washing structure (as a whole) 12. In thecollector structure 10, there is collector space 13 in each separatecollector 23 having lower small outlet 17. The plastic through-passagestructure 11 has a plurality of through-spaces 14 in the funnel portionand 19 in the wall surface-coating portion. The irregularly-shapedwall-structure 18 (inner wall-structure of the through-passage) includesa unifying ring-portion 20 either wedged or fused in close-fitrelationship with downwardly-extending tubular portion 21 separable fromother adjacent downwardly-extending tubular portions by virtue of thescore-line 22 seen in each of FIGS. 1 through 4. Thedownwardly-extending tubular portion 21 is viewable in transversecross-section of FIGS. 5, 6, and 7, and unifying ring portions 20, 20a,and 20b, and through-passage inner-wall structures 18, 18a, and 18b, andliquid-retaining spaces 19, 19a, and 19b, and central bore spaces 25,25a, and 25b being also viewable in these Figures, for the embodiments26, 27, and 28 respectively. Each separate downwardly-extendingfunnel-like structure 24 of the washing structure 12 extends from aliquid container 41 having liquid containing space 16, with the outersupporting wall's base being seated as shown in FIGS. 1 and 2 snuglycircumscribing ledge 39 and on seat (upper face) 40. The basebottom-face of inner-wall structure 18 preferably as face 38 anglesradially inwardly and downwardly, as seen in FIGS. 2 and 3, and likewisethe inner face of the collector-structure 23 downwardly extendingfollows the angularly downwardly and radially inwardly-extendingstructure 37, whereby liquid tends to flow in a radially inward orcentral direction into outlet aperture 17, the lower portion or faces 38and other lower portions of the wall 18 never-the-less remaining incontact with such liquid and by capillary action serving to retainliquid within spaces 19 and 25, and 13.

The alternate embodiment of FIG. 4 is a unitary structure comparable tothe two separate apparatuses of FIG. 3, having inner walls 18' of thethrough-passage structure 23', with inner central space 25' andperipheral inner spaces 19' and collector space 13' adjacent outletaperture 17', formed within tubular collector-structure such astypically the downwardly-extending conical wall 37'. Theretainer-structure portion has a wall-retaining flange 39' around whicha washing structure 12 (of FIG. 2) would seat onto seat 40', thisembodiment also preferably having a score line 22', and recessed upperends of walls 18' thus providing fill-space 14 preventing likelihood ofoverflow into adjacent through-passages.

FIGS. 8 and 9 illustrate embodiments each of which have a singlethrough-passage and structure thereof, as through-passage structure 29and through-passage structure 30. The through-passage structure 29 hastypically the insert ring and wall (inner) structure embodiment 26 (ofFIG. 5), and collector lower conical wall structure 37a with itsaperture 32 of the overall through-passage structure having upper wall31 and upper funnel-space 25, and collector space 13a.

The alternate embodiment 30 capitalizes principally on the fact ofreduced wasted-space (in a sense), together with having a sufficientlysmall tubular space 19c as to effect capillary action, and the smallvolume of liquid being more easily and completely depleted of, forexample, antigens carried within liquid within that space because of theclose proximity of all antigen bodies to wall surface(s) of thesurrounding inner tubular walls of the passage tubular space 19c; aswith other embodiments, the upper portion of the through-passagestructure has the funnel-forming wall 33 forming funnel-space 25" withthe funnel (conical) wall structure 38 having inlet 35 to the tubularspace 19c. As in the FIG. 8 embodiment, the embodiment 30 has outletaperture 36 formed within the conical wall 37b.

The method of use of the present invention is novel as is theapparatus(es) of the invention, making possible the elimination oftedious and slow procedures. It should be noted firstly, that thethrough-passage structure 11 of any of FIGS. 1, 2, or 3, may be utilizedalone as the sole inventive structure, while there are additionaladvantages to be obtained by the combination with the collectorstructure 10 and/or the washing structure 12. Accordingly, aprecalculated and thus predetermined and measured amount of, forexample, antigen-containing liquid may be introduced into funnel space14 in an amount that will fill at-least a lower portion of the spaces19, and 25, buw which normally will be insufficient in weight tonormally (at least to any signficant extent) flow-out through the lowerend as drops or droplets, i.e. the antigen-containing liquid being heldby capilliary action in the spaces in close proximity to the wallsurface area onto which antigens attach to the plastic walls. It shouldbe further noted that heretofore the walls to which the antigensattached were the container walls of a immunological plate, and otherapparatuses such as diluters and/or washing apparatuses were not usedfor such function. In this invention, the flow-through apparatus is infact the antigen-collector--i.e. the surface area to which antigensattach during incubation. After an incubation period, which because ofthe large surface area relative to the small volume ofantigen-containing vehicle-liquid, obtains a higly efficient coating, awashing liquid is introduced in any needed quantity and as such isintroduced, the weight thereof causes the same to move downwardly on topof the prior vehicle, causing the antigen-depleted vehicle-liquid tobecome forced-out of the lower spaces 19 and 25. Thereafter, a nextreagent is added, such as adding serum in the same precalculated andmeasured amount--such forcing-out and replacing the heretofore-retainedwashing water; thereafter, an incubation period is allowed forattachment of antibodies to respective ones of the attached antigens.Thereafter, there is again introduced washing water, followed byintroducing an enzyme-labeled immunoglobulins reagent which by itsweight replaces the washing water, after which there is anotherincubation period, followed by another washing, followed by introducinga substrate reagent, followed by measuring absorption byspectrophotometer. It is to be understood that this is merely anillustrative example, and that instead of this entire procedure, aradioisotope or the like may be added as one step, followed byincubation, and by then washing, and then separating that particularthrough-passage downwardly-extending structure from adjacent ones andthen testing for radio-activity thereof, for example.

The same procedure would be conducted when utilizing the combination ofFIG. 3, with or without the preferred washing structure 12 of FIG. 2during washing, and likewise the same procedure can be followed with theembodiments of FIGS. 4, 6 and 7, as well as with the embodiments ofFIGS. 8 and 9 respectively.

The utilization of the collector structure 10 or of the embodiments ofFIG. 4 or FIG. 8 (embodiment 29) or FIG. 9 (embodiment 30), results inretaining a larger column-height of water and/or vehicule-liquid orreagent within the spaces 19, 25 and 13, or 19', 25', and 13' or 19c,for example--there being no separate collector as-such for embodiment30.

The funnel spaces 14, 14', 14" and 14'" serve as volumous spaces intowhich the liquid may be easily introduced in the precauculated andmeasured amount, or during washing, without likelihood or overflowingthe upper-wall edges thereof, thus avoiding contamination. In likemanner, it will be noted that the apertures 17, 17', 32 and 36 aresupported above the level of a supporting surface that would be locatedtherebeneath during use. For use in a test-tube rack, the embodiments 29and 30 have upper flanges, illustrated as a preferred embodiment featurethereof but optional, as flanges 42 and 42'.

When not utilizing the specific washer of this invention, conventionalor otherwise-desirable washing apparatuses and procedures may beutilized.

The assay systems described above, and apparatus(es) and combinationsthereof may be utilized for typically the following known general testmethods, adapted as set forth above:

(a) Enzyme-linked immunosorbent assay, non-competitive, for thedetermination of antigens;

(b) Enzyme-linked immunosorbent assay, non-competitive, for thedetermination of antibodies;

(c) Enzyme-linked immunosorbent assay, competitive, for thedetermination of antigens;

(d) Radioimmunoassay, non-competitive, solid phase, for thedetermination of antigens;

(e) Radioimmunoassay, non-competitive, solid phase, for thedetermination of antibodies;

(f) Radioimmunoassay, competitive, solid phase, for the determination ofantigens;

(g) Competitive protein binding radioassay, solid phase;

(h) Non-competitive protein binding radioassay, solid phase;

(i) Competitive protein binding enzymoassay, solid phase; and

(j) Non-competitive protein binding enzymoassay, solid phase; these notbeing exclusive nor limiting of the scope of the invention. Theabove-note procedures (a) throgh (j) would be typically conducted asfollow:

Method (a):

1. Coat the walls (18 or 18', etc.) of the through-passage with specificantibodies;

2. Place a fixed volume of serum dilutions (or other specimens) andstandards in each well(through-passage) of the assay system;

3. Incubate;

4. Wash; & dry;

5. Add a fixed volume of a solution of enzyme labelled antibodies toeach well.

6. Incubate.

7. Wash; & dry;

8. Add a fixed volume of a chromogenic reagent to each well.

9. Read the result--as shall be noted below.

Method (b):

1. Coat the wells of an assay system with corresponding antigens;

2. Place a fixed volume of serum dilutions (or other specimens) andstandards in each well of the assay system.

3. Incubate.

4. Wash; and dry;

5. Add a fixed volume of a solution of enzyme labelled anti-globulinantibodies to each well.

6. Incubate;

7. Wash and dry;

8. Add a fixed volume of a chromogenic reagent to each well;

9. Read the result.

Method (c):

1. Coat the wells of an assay system with a fixed amount of antibodies.

2. Place a fixed volume of serum dilutions (or other specimens)standards to each well of the assay system.

3. Add a fixed volume of a solution enzyme labelled antigens to eachwell.

4. Incubate.

5. Wash and dry;

6. Add a fixed volume of chromogenic reagent to each well.

7. Read the result.

Method D:

1. Coat the wells of an assay system with specific antibodies;

2. Place a fixed volume of serum dilutions (or other specimens) andstandards into each well of the assay system.

3. Incubate.

4. Wash and dry.

5. Add a fixed volume of a solution of radio-labelled antibodies to eachwell.

6. Incubate.

7. Wash.

8. Count the radioactivity of each well.

Method E:

1. Coat the wells of an assay system with corresponding antigens;

2. Place a fixed volume of serum dilutions (or other specimens) andstandards into each well of the assay system;

3. Incubate;

4. Wash and dry;

5. Add a fixed volume of a solution of radiolabelled anti-globulinantibodies to each well;

6. Incubate;

7. Wash;

8. Count the radioactivity of each well.

Method F:

1. Coat the wells of an assay system with a fixed amount of specificantibodies;

2. Place a fixed volume of diluted serum (or other specimens) andstandards into each well of the assay system;

3. Add a fixed volume of a solution of radio-labelled antigens to eachwell;

4. Incubate;

5. Wash;

6. Count the radioactivity of each well.

Method G:

Follow the same procedure as for Method F, except:

(1) Use binding protein instead of antibodies; and

(2) the substance to be measured does not function as an antigen. MethodH: The procedure is the same as that of Method D, except for thedifferences noted in method G-above. Method I: Competitive protein . . .method, the procedure is the same as that for Method C-above, with theexceptions of Method G; Method J: The procedure is the same as anenzymoassay of Method A-above, with the exceptions of the Method G.

In the use of the apparatus(es) of the invention, the entire stackedcombination of FIG. 1 may advantageously be utilized as follow. If thesame material is to be added to all wells (through-passages) during thefirst step, and similarly whenever for any subsequent step the samematerial is to be added to all wells, then it may be poured collectivelyinto the space 16 in order to avoid having to individually place thesame into each separately which would require considerable time. On theother hand, if after adding the different initial material to differentones of the wells, the same (common) material(s) and/or treatments arefollowed for all, the initial different materials may be added to thefunnel space 14 of FIG. 3 combination or to the funnel space 14' of theFIG. 4 combination, and thereafter the apparatus of the washingstructure 12 may be added (to obtain the FIG. 1 combination) forsubsequent procedures in which the treatments of all wells are the same,and/or until the procedure differs again.

In order to effectively read the test results of enzymoassays for thepresent invention and apparatus thereof, any of the following proceduresmay be followed alternatively:

1. The color of the solution is assayed by a spectrophotometer after theenzyme activity is stopped; or

2. The color of the solution is inspected by eyes after the enzymeactivity is stopped; or

3. The solution is drained into a white absorbent paper containing achemical reagent that stops the enzyme activity, and the resulting coloris inspected by ones eyes.

Draining may be effected advantageously by touching the absorbent papersurface to the aperture 17 or 17' or 32 or 36.

While the breadth of transverse cross-sectional measurements of spaces19 have not been specified, it is advantageous that such be small enoughin nature as to effect capilliary action, but such small dimension isnot essential except in the embodiment 30, the large surface arearelative to liquid volume being an advantage in any event.

For the various embodiments of FIGS. 1 through 4 and 7 and 8, thewell-space (funnel-space) 14, 14', 14", and 14'", have a transverse(horizontal) cross-sectional width or diameter of typically from 0.5 to3.0 cm., preferably from about 0.5 cm. to 2.0 cm.; with an upperwell-depth (of these spaces 14, . . . ) of from about 0.2 cm. to 5.0cm., preferably from about 0.3 cm. to about 2.0 cm.; and the diameteracross space 19 & 25 ranges from about 0.3 cm. to about 2.0 cm.,preferably from about 0.5 cm. to about 1.0 cm., at a depth (length ofwalls 18) from about 0.3 cm. to about 3.0 cm., preferably 0.5 cm. toaobut 1.0 cm.; and apertures 17, 17', 32 and 36 each range from about0.05 cm. to about 0.5 cm., preferably from about 0.1 cm. to about 0.3cm. The dimensions of 19' and 19a and 19b correspond to 19; and of 25aand 25b, etc., to 25; and of 19c to 36.

Aside from advantages already pointed out above, and aside from alreadystated objects, it might be noted that particular advantages include:

1. Smaller volume of test material, reagents (enzyme and antisera) andthe like, are required.

2. More effective coating is obtained.

3. Incubation is obtained in a shorter period of time.

4. The tests conventionally known, become more sensitive by use of theinventive apparatus(es) and procedure(s).

5. Easier and more effective washing are obtained.

6. The plates may be "pre-loaded" (pre-treated) with reagents, merelyrequiring the subsequent-adding of the final material(s) and washingswhere required.

it is to be understood that the invention is not limited to the specificembodiment illustrated, but include other embodiments within the scopeof the appended claims, together with modifications, substitution ofequivalents, and the like, to the extent that such would be obvious to aperson of ordinary skill.

I claim: .[.
 1. An immunological testing device comprising: a plasticstructure having upper and lower open ends, having a through-passage ofpredetermined small cross-sectional area sufficiently small to retainliquid by capillary action within space thereof at at-leastsubstantially an intermediate portion of a length thereof, and theplastic structure being elongated along a longitudinal axis of thethrough-passage, the ratio of the wall surface area of saidthrough-passage being larger than the cross-sectional area of saidintermediate portion, and in which said plastic structure has formedtherein an enlarged funnel structure in continuous flow-relationshipwith the upper end of the intermediate portion of the through-passage ofsaid predetermined small cross-sectional area..]. .[.2. An immunologicaltesting device of claim 1, in which said plastic structure has only asingle through-passage..]. .[.3. An immunological testing device ofclaim 1, in which said plastic structure includes a plurality of saidthrough-passages arranged in substantially parallel-flow relationship;and tubular collector-structure forming a common collecting space atlower-end outlets of said plurality..]. .[.4. An immunological testingdevice of claim 1, including a washing structure having a liquidcontaining structure with a plurality of spaced-apart funnel-outlets,and in which said plastic structure includes a plurality of saidthrough-passages and of said enlarged funnel structures, and washingstructure being seatable onto an upper portion of said enlarged funnelstructures with each one respectively of the enlarged funnel structurespositioned for receiving liquid flow from at least one of saidspaced-apart funnel-outlets, the spaced-apart funnel-outlets therebyfeeding washing liquid to separate ones of said enlarged funnelstructures whereby through-passages associated with respective ones ofeach enlarged funnel structure are concurrently washable so as to bedevoid of contamination between separate ones of the enlarged funnelstructures..]. .[.5. An immunological testing device of claim 1, inwhich said plastic structure includes a plurality of saidthrough-passages arranged in substantially parallel-flow relationshipand in which through-flow spaces of said plurality of saidthrough-passages are in flow-communication with one-another; andincluding a washing structure having a liquid containing structure witha plurality of spaced-apart funnel-outlets, said washing structure beingseatable onto an upper portion of structure of a plurality of saidenlarged funnel structure with each one respectively of the enlargedfunnel structures positioned for receiving liquid flow from at least oneof said spaced-apart funnel-outlets, the spaced-apart funnel-outletsthereby feeding washing liquid to separate ones of said enlarged funnelstructures whereby through-passages associated with respective ones ofeach enlarged funnel structure are concurrently washable so as to bedevoid of contamination between separate ones of the enlarged funnelstructures..]. .[.6. An immunological testing device of claim 1including a plurality of said enlarged funnel structure and pluralitiesof said through-passages, through-passages of different enlarged funnelstructures being in segregated non-flow relationship to one-another..]..[.7. An immunological testing device of claim 5, including means fordetaching individual sets of an enlarged funnel structure and associatedplurality of through-passages thereof, from other ones of enlargedfunnel structures and associated through-passages thereof..]. .[.8. Animmunological testing device of claim 7, in which said means fordetaching comprises scored structure adapted for ease of severingstructures from one-another..]. .[.9. An immunological testing device ofclaim 3, in which said tubular collector structure has a lower outletaperture of predetermined small dimensional cross-section sufficientlysmall to effect retaining a drop of liquid within said common collectingspace when devoid of liquid weight of additional liquid above saidintermediate portion within said enlarged funnel structure..]. .[.10. Animmunological testing device of claim 3, in which spaces of theplurality of said through-passages are in common communication alonglongitudinal lengths thereof within a space formed centrallytherebetween and interconnecting the through-passages of the pluralityof said through-passages..]. .[.11. An immunological testing device ofclaim 10, in which said tubular collector structure has a lower outletaperture of predetermined small dimensional cross-section sufficientlysmall to effect retaining a drop of liquid within said common collectingspace when devoid of liquid weight of additional liquid above saidintermediate portion within said enlarged funnel structure..]. .Iadd.12. An immunological testing device comprising a plastic receptaclestructure having upper and lower apertures and a longitudinalthrough-passage continuous between the upper and lower apertures, saidlongitudinal through-passage having upper and lower portions, said lowerportion having a first predetermined transverse cross-sectional areasufficiently small to retain water by capillary action, and said lowerportion of said through passage being defined by inner wall-structuresthat substantially increase the extent of the circumscribing innersurface of said plastic receptacle structure and make an irregular wallsurface for a significant axial extent of said lower portion, whilesubstantially reducing the volume of said lower portion as compared tothe volume of the said lower portion without said inner wall-structures,said upper portion of said through-passage having a second predeterminedtransverse cross-sectional area of a magnitude greater than said firstpredetermined transverse cross-sectional area, and said upper portionbeing in continuous flow relation with said lower portion of saidthrough-passage. .Iaddend..Iadd.
 13. An immunological testing device asclaimed in claim 12, in which said plastic receptacle structure has onlya single longitudinal through-passage. .Iaddend..Iadd.
 14. Animmunological testing device as claimed in claim 12 which has aplurality of said plastic receptacle structures each having alongitudinal through-passage arranged in substantially parallel-flowrelationship with one another. .Iaddend..Iadd.
 15. An immunologicaltesting device as claimed in claim 12 which has a plurality of saidplastic receptacle structures each having a longitudinal through-passagearranged in substantially parallel-flow relationship with one another,and a washing structure having a plurality of spaced-apart funnelmembers, said washing structure being seatable on said plurality ofplastic receptacles to hold said funnel members above thethrough-passages of said plastic receptacle structures, whereby whenliquid is poured into said washing structure it will pass through saidfunnel members and into the through-passages of said plastic receptaclestructures simultaneously without danger of contamination between thevarious ones of said receptacle structures. .Iaddend..Iadd.
 16. Animmunological testing device as claimed in claim 1 having a plurality ofsaid plastic receptacle structures detachably mounted together in spacedrelationship. .Iaddend. .Iadd.
 17. An immunological testing device asclaimed in claim 12 in which said plastic receptacle structure includesa collector structure having a downwardly and inwardly-tapered conicalsurface in communication with said lower portion of said through-passageand said lower aperture. .Iaddend..Iadd.
 18. An immunological testingdevice as claimed in claim 12 in which said lower aperture is of apredetermined dimensional cross-section sufficiently small to effectretention of liquid within the lower portion of said through-passage..Iaddend.